Histologic Progression During Treatment with Radiofrequency Ablation is Associated with Poorer Outcomes of Endoscopic Eradication Therapy

AGA Abstracts

(each 2 cm apart) above the LES was compared. In patients with BE, visual analysis of the low impedance on HREMI (visual low impedance [VLI]) was assessed. The impedance values at each impedance sensor were also plotted. Using the slope between each impedance value an inflection point was noted. The sensor prior to the inflection point was used to measure the extent of plotted low impedance [PLI] (Figure 1). Lengths of VLI and PLI were correlated to the endoscopic length of Barrett's esophagus by the Prague score, C (circumferential) and M (maximal) extent, measured by a single endoscopist (MSS). Results: 45 patients were included (16 BE-10 male, mean age 63, mean BE Prague score C4M7; 19 esophagitis-8 male, age 54; 10 volunteers-8 male, age 31). BE patients had significantly lower DEI at the 1st, 2nd, and 3rd sensors above the LES (0.81±0.20, 0.97±0.27, 1.37±0.45) compared to the healthy volunteers (6.94±0.99, 8.20±0.73, 8.73±0.60; p<0.01). DEI was significantly lower for BE patients than esophagitis patients (2.01±0.51, 2.49±0.56, 2.98±0.65) at the 1st and 2nd sensors (p<0.01). Esophagitis patients had significantly lower DEI than healthy volunteers, but results were higher than the BE group; i.e., BE<
Figure 2: Odds Ratio for esophagitis after bariatric surgery compared to before surgery, I sq= 87, Tau sq= 0. 3, 7 studies, 803 pts

Su1057 VOLUMETRIC LASER ENDOMICROSCOPY FINDINGS CAN RISK STRATIFY PATIENTS FOR RECURRENCE FOLLOWING ENDOSCOPIC TREATMENT OF BARRETT'S ESOPHAGUS Michael S. Smith, Vani J. Konda, Arvind J. Trindade, Brooks D. Cash Background: Volumetric Laser Endomicroscopy (VLE) provides high-resolution, cross-sectional views of the esophagus using optical coherence tomography (OCT) technology. This technique scans a contiguous 6 cm esophageal segment in 90 seconds, imaging to a depth of 3 mm with a resolution of 7 microns. Standard white light endoscopy (WLE) is an enface imaging system where tissue evaluation is limited to the mucosal surface. It is hypothesized that the additional, cross-sectional, information that VLE provides enhances detection of disease, including dysplasia and sub-epithelial disease. Studies to date have focused on its utility in patients with Barrett's esophagus (BE). Methods: A US-based multicenter registry prospectively collected data on 1,000 patients when VLE was used during endoscopic esophageal evaluation. All procedures used the NvisionVLE® Imaging System (NinePoint Medical, Bedford, MA). Each patient could have up to four procedures entered in the registry, with timing at the discretion of the endoscopist. Demographic, procedural, and pathology data were collected and de-identified prior to analysis. This analysis examines the use of VLE in a post-treatment population. Results: Out of 1000 registry patients, 130 patients were designated as undergoing post treatment surveillance and were found to have no evidence of BE under WLE. Tissue acquisition via forceps biopsy was performed on 120 of these patients, at the time of index endoscopy and/or during any follow up procedure. This cohort had a mean surveillance interval of 369 days between initial endoscopy and their most recent follow up procedure . Ultimately BE was confirmed on biopsies in 25 patients (21%, 25/120), 17 non-dysplastic (14.2%, 17/120) and 8 dysplastic (6.7%, 8/120). In the 64 patients (49%, 64/120) who had an index post treatment VLE without concerning findings, 58 patients had tissue acquired during a mean follow up of 314 days, of these only 8 patients (14%, 8/58) had BE , 7 (10.9%, 7/58) non-dysplastic and 1 (1.6%, 1/58) with low grade dysplasia. Conclusions: Following successful visual eradication of BE, a VLE scan was found to be clinically beneficial in that the absence of concerning findings strongly predicted complete remission of intestinal metaplasia 86%, (50/58) and dysplasia 98% (57/58) during both index and follow-up surveillance endoscopies. Current practice includes frequent post-ablation surveillance, especially in the first year after ablation. These data suggest that a "negative" VLE post completion oftreatment may allow for extended intervals between surveillance procedures without sacrificing patient safety. Dysplasia Detection By VLE Procedure Results

Figure 1: Analysis of extent of low impedance in distal esophagus by HREMI in patient with BE

Su1059 HISTOLOGIC PROGRESSION DURING TREATMENT WITH RADIOFREQUENCY ABLATION IS ASSOCIATED WITH POORER OUTCOMES OF ENDOSCOPIC ERADICATION THERAPY Athidi Guthikonda, Cary C. Cotton, Audrey O. Chang, Swathi Eluri, Ryan D. Madanick, Melissa Spacek, Susan E. Moist, Kathleen Ferrell, Evan S. Dellon, Nicholas J. Shaheen BACKGROUND - Prior Radiofrequency Ablation (RFA)studies use baseline histologic grade to stratify outcomes of Barrett's esophagus. However, during therapy, patients maybe found to have higher histologic grade than that at initiation of therapy. Outcomes among these patients to treatment and in post-ablation surveillance are not well-described. AIMS - To describe the clinical outcomes and risk factors associated with finding increased histologic grade duringtreatment of Barrett's esophagus. METHODS - We performed a retrospective cohort study of 322 patients at an academic referral center with first treatment of RFA for Barrett's esophagus from 2006-2014. Complete eradication of intestinal metaplasia (CEIM) was defined as histologic and endoscopic remission of IM. Progression during treatment was defined as any endoscopy prior to CEIM in which a mucosal irregularity prompted either endoscopic mucosal resection (EMR) or forceps biopsy which showed a higher histologic grade than that known at first RFA treatment. We performed Poisson rates regression to estimate the rate ratio (RR) of achieving CEIM with multivariable adjustment for baseline histologic grade, baseline Prague M segment length, and known nodularity at baseline. We estimated the prevalence odds ratio (POR) for increasing histologic grade during treatment as a function of baseline and treatment characteristics. RESULTS - During treatment, 15 of 311 patients (5%) had biopsy or EMR with higher histologic grade than that known at initiation of treatment (Figure 1). Though 7 of the 15 (47%) of patients with increase in grade achieved CEIM, they did so at a lower rate (RR0.39, 95% CL 0.18 - 0.82) than all treated patients (257 of 296, 87%). Of the 8 not achieving CEIM, all but one who progressed to invasive cancer and esophagectomy were undergoing active treatment. This difference persisted, but was attenuated (adjusted RR0.52, 95% CL 0.24 - 1.12) by adjustment for baseline characteristics. Longer Barrett's segment length (POR per centimeter 1.15, 95% CL 1.02 - 1.31) was associated with greater risk for progression during treatment, while nodularity at baseline (POR 0.56, 95% CL 0.12 - 2.54) and baseline histologic grade (POR 0.64, 95% CL 0.30 - 1.34) werenot risk factors for increasing grade during treatment. CONCLUSION - In this large cohort of patients at an academic center undergoing RFA for Barrett's esophagus, progression during treatment with RFA occurred in 5% of patients and portended a worse outcome. Longer Barrett's segment length was a strong risk factor for progression during treatment. Patients with progression during treatment were less likely to achieve CEIM than patients without.

Su1058 DISTAL ESOPHAGEAL IMPEDANCE MEASUREMENTS DURING HIGH RESOLUTION ESOPHAGEAL MANOMETRY WITH IMPEDANCE (HREMI) PREDICTS PRESENCE AND LENGTH OF BARRETT'S ESOPHAGUS (BE) Rahul Kataria, Benjamin Rosenfeld, Zubair A. Malik, Martha J. Harrison, Ron Schey, Henry P. Parkman, Michael S. Smith Introduction: Barrett's esophagus (BE) is characterized by intestinal metaplasia in the distal esophagus. Multichannel intraluminal impedance with pH monitoring (MII-pH), used to assess gastroesophageal reflux, has shown lower distal esophageal impedance (DEI) in patients with esophagitis; use of HREMI for this purpose has limited data. The aims of this study are to: 1) compare DEI using HREMI in patients with BE, esophagitis, and healthy volunteers; and 2) correlate the length of low DEI in patients with BE using HREMI to the length of endoscopically measured BE. Methods: A retrospective review from 2013 to 2016 was performed. Patients with an EGD and biopsy proven BE or esophagitis, and HREMI within 120 days of their EGD were included. Patients with achalasia or previously treated BE were excluded. 10 healthy volunteers had HREMI. DEI was calculated from HREMI using a 30 second segment prior to wet swallows. Readings from the first three impedance sensors

AGA Abstracts

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regimens was at least 2 weeks. On day 7 of each regimen, subjects underwent 24-hour intragastric pH monitoring. Serum gastrin levels were measured on the morning of day 7. Results: Median pH 4 holding time ratios (HTRs) (and ranges) attained by VPZ 20 mg q.d.[GH1] was 99% (95-100%), which was the longest of the three regimens, followed by VPZ 10 mg q.d. + lafutidine 10 mg q.d. at 88% (76-93%) and VPZ 10 mg at 82% (4788%). Median pH 4 HTRs (and ranges) during nighttime (from 10 pm to 8 am) with the respective regimens were 100% (100-100%), 100% (95-100%) and 94% (29-100%). The incidence of NAB with the three regimens was 0%, 8% and 38%, respectively, and serum gastrin levels were 504pg/ml (400-812pg/ml), 323pg/ml (196-521pg/ml), and 420pg/ml (173-508pg/ml), respectively. Conclusion Vonoprazan 20 mg q.d. resulted in complete acid inhibition throughout a 24-hour period, and inevitably led to a higher gastrin serum level. Vonoprazan 10 mg q.d. did not achieve sufficient gastric acid suppression. However, the concomitant administration of VPZ 10 mg and lafutidine 10 mg did achieve sufficient acid inhibition, which was superior to that achieved by 10 mg of VPZ alone, and decreased NAB without an increase in serum gastrin levels. Although acid inhibition by concomitant administration of VPZ 10 mg and lafutidine 10 mg was inferior to that by VPZ 20 mg, the former regimen is recommended for maintenance therapy for acid-related disorders because it induces clinically sufficient acid inhibition without the induction of abnormal hypergastrinemia. (UMIN22290)

Figure 1. (a) Study flow outline. Data includes the number of participants enrolled and the number of participants who completed the study. (b) Schematic demonstration of the study protocol. Subjects received three regimens in a randomized crossover manner: (1) vonoprazan (VPZ) 20 mg qd for 7 days; (2) VPZ 10 mg qd + Lafutidine 10mg qd for 7 days; (3) VPZ 10 mg qd for 7 days. Twenty-four-hour (24-h) intragastric pH monitoring was performed on Day 7 in each regimen. The washout period between regimens was at least 2 weeks.

Figure 1. Distribution of Worst Known Histologic Grade Before and After First RFA Treatment Among those Treated for at Least One Year or Until Complete Eradication of Intestinal Metaplasia or Progression.

Su1060 ACID INHIBITION ATTAINED BY CONCOMITANT ADMINISTRATION OF LAFUTIDINE WITH VONOPRAZAN WITH REFERENCE TO SERUM GASTRIN LEVELS Takahiro Suzuki, Mihoko Yamade, Takuma Kagami, Hitomi Ichikawa, Takahiro Uotani, Yasushi Hamaya, Moriya Iwaizumi, Satoshi Osawa, Ken Sugimoto, Hiroaki Miyajima, Takahisa Furuta Backgrounds/Aims: The treatment of acid-related diseases, such as gastro-esophageal reflux disease (GERD), requires sufficient gastric acid inhibition. Proton pump inhibitors (PPIs) do not always induce sufficient inhibition throughout a 24-hour period, a situation known as nocturnal acid breakthrough (NAB). The novel acid inhibitor vonoprazan (VPZ), which is categorized as a potassium-competitive acid blocker, has been reported to produce potent acid inhibition throughout a 24-hour period at a dose of 20 mg. However, the hypergastrinemia induced by VPZ confers a risk of carcinoid tumor. As a result, the recommended maintenance dose of VPZ in Japan is now 10 mg, but this is insufficient to prevent NAB. H2 receptor antagonists (H2RA) are known to be useful for NAB when co-administered with a PPI. However, it is unclear whether an H2RA is useful for NAB when given with 10 mg of VPZ. Therefore, we evaluated the usefulness of the H2RA lafutidine in acid suppression when given with VPZ 10 mg q.d. with reference to serum gastric levels. Methods: Fifteen young, healthy, H. pylori-negative Japanese volunteers received three different regimens for 1 week each in a randomized, crossover manner as follows: (1) VPZ 20 mg q.d., (2) VPZ 10 mg q.d. + lafutidine 10 mg q.d. and (3) VPZ 10 mg q.d. The washout period between

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AGA Abstracts

AGA Abstracts

Table 1. Baseline Characteristics Among Patients with Progression during Treatment and Without